1.Identification of a novel germline BRCA2 variant in a male with breast cancer.
Chinese Journal of Medical Genetics 2022;39(3):330-333
OBJECTIVE:
To explore the genetic basis for a male with breast cancer and a sister who had deceased of the disease.
METHODS:
Medical and family history of the proband was collected. Next-generation sequencing was carried out to detect potential variant associated with breast cancer, and Sanger sequencing was used to verify the result.
RESULTS:
The proband was found to harbor a novel heterozygous c.6018dupT variant of the BRCA2 gene which may cause premature termination of mRNA translation, resulting in a truncated protein. Combined with the family history, the variant was deduced to be a germline mutation. Based on the American College of Medical Genetics and Genomics standards and guidelines, c.6018dupT variant of BRCA2 gene was predicted to be pathogenic (PVS1+PM1/2+PP4).
CONCLUSION
The germline variant of the BRCA2 gene probably underlay the breast cancer in this pedigree.
BRCA2 Protein/genetics*
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Breast Neoplasms, Male/genetics*
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Genes, BRCA2
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Genomics
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Germ Cells
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Germ-Line Mutation
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Humans
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Male
4.Analysis of BRCA2 gene mutations among familial and/or early-onset breast cancer patients in eastern Shandong of China.
Zhong-liang MA ; Ming-zhi CAO ; Wen-feng LI
Chinese Journal of Medical Genetics 2008;25(2):195-198
OBJECTIVETo investigate the prevalence of BRCA2 gene mutations among familial and/or early-onset breast cancer patients in eastern Shandong of China.
METHODSFifty-two familial and/or early-onset breast cancer patients from unrelated family were analyzed. Genomic DNA was collected from the peripheral blood mononuclear cells, the coding sequences and exon-intron boundaries of BRCA2 gene were screened using denaturing high performance liquid chromatography (DHPLC), and the abnormal fragments were confirmed with direct DNA sequencing.
RESULTSThree mutations (5.8%) in BRCA2 gene were identified. They were 2001del TTAT, 4099C to T and 5873C to A. To our knowledge, all of them were firstly found in Chinese population. Furthermore, all the three mutations (12%) were identified in familial breast cancer patients, and none was in the early-onset patients.
CONCLUSIONBRCA2 may play an important role in the familial breast cancer in eastern Shandong Chinese population, but not in the early-onset breast cancer. It is necessary to give genetic test to familial breast cancer patients in this population.
Adult ; BRCA2 Protein ; genetics ; Breast Neoplasms ; genetics ; China ; Chromatography, High Pressure Liquid ; Female ; Humans ; Mutation ; Polymerase Chain Reaction
5.BRCA1 and BRCA2 gene mutations of familial breast cancer from Shanghai in China.
Chuan-gui SONG ; Zhen HU ; Wen-tao YUAN ; Gen-hong DI ; Zhen-zhou SHEN ; Wei HUANG ; Zhi-min SHAO
Chinese Journal of Medical Genetics 2006;23(1):27-31
OBJECTIVETo investigate the prevalence of BRCA1 and BRCA2 gene mutations among breast cancer patients with affected relatives in Shanghai of China.
METHODSThirty-five breast cancer patients who had at least one first-degree relative affected were analyzed, among whom 13 patients suffered from breast cancer at age of less than 40 years. A comprehensive BRCA1 and BRCA2 mutation analysis was performed through denaturing high-performance liquid chromatography (DHPLC) and subsequent DNA direct sequencing.
RESULTSFour mutations in BRCA1 gene, including 2 novel splice-site mutations (IVS17-1G>T, IVS21+1G>C) and 2 frameshift mutations (1100delAT; 5640delA) were identified. One frameshift mutation (5802delAATT) was detected in exon 11 of BRCA2. Additional 12 novel single nucleotide polymorphisms(SNPs) were detected, including a novel unclassified variant and 7 novel intronic variants in BRCA1, and 4 novel intronic variants in BRCA2, with which all caused no alteration of amino acid coding. The mutation frequency of BRCA1 and BRCA2 in patients with family history was 11.4% and 2.9%, respectively.
CONCLUSIONTwo novel mutations in BRCA1 may be mutations characterized to familial breast cancer of Chinese Shanghai population. The BRCA2 may contribute to mutation less than BRCA1 in familial breast cancer. Our data contribute to information on mutation spectrum of BRCA gene in Chinese population and also offer a recommended screening mode for clinical genetic testing policy in China.
Asian Continental Ancestry Group ; genetics ; BRCA1 Protein ; genetics ; BRCA2 Protein ; genetics ; Breast Neoplasms ; genetics ; China ; DNA, Neoplasm ; analysis ; Family Health ; Female ; Humans ; Point Mutation ; Polymorphism, Single Nucleotide
6.Progress in molecular genetics of correlating genes of breast cancer.
Yang WU ; Li YANG ; Yuquan WEI
Chinese Journal of Medical Genetics 2002;19(2):152-155
Good progress has been made in the researches on correlating genes of breast cancer in recent years. Quite a few kinds of genes such as susceptibility gene, oncogene and tumor suppressor genes have been found with implications for diagnosis, therapy and prognosis. Abnormality of breast cancer susceptibility gene (BRCA) is of great significance, especially in the development of breast cancer.
BRCA1 Protein
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genetics
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BRCA2 Protein
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genetics
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Breast Neoplasms
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genetics
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Cyclin-Dependent Kinase Inhibitor p16
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genetics
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Cyclin-Dependent Kinase Inhibitor p21
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Cyclins
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genetics
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Female
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Humans
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Mutation
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Neoplasm Proteins
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genetics
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Proto-Oncogene Proteins
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genetics
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Tumor Suppressor Protein p53
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genetics
7.Effect of BRCA2 mutation on familial breast cancer survival: A systematic review and meta-analysis.
Jun SHAO ; Jie YANG ; Jun-nai WANG ; Long QIAO ; Wei FAN ; Qing-lei GAO ; Yao-jun FENG
Journal of Huazhong University of Science and Technology (Medical Sciences) 2015;35(5):629-634
Reports of BRCA2 genetic mutations on the prognosis of familial breast cancer (BC) patients have been contradictory. True difference in survival, if it exists, would have important implications for genetic counseling and in treatment of hereditary BC. The purpose of this study was to compare overall survival rate (OSR) among BRCA2 mutation carriers, non-carriers and sporadic BC patients. We searched the PUBMED and EMBASE databases and retrieved 4529 articles using keywords that included breast cancer, BRCA, prognosis and survival. Nine articles were selected for systematic review and among them 6 were included in our meta-analysis. We used the fixed and random effect models to calculate the summary odds ratio (OR) and corresponding 95% confidence interval (CI). BRCA2 mutation carriers had significantly higher long-term OSR than non-carriers (OR=0.69 [95% CI=0.5-0.95]), while both short-term and long-term OSR of BRCA2 mutation carriers did not differ from those of patients with sporadic disease (OR=1.11 [95% CI=0.74-1.65]; 0.85 [95% CI=0.38-1.94], respectively). For BC-specific survival rate (BCSSR), BRCA2 mutation carriers had a similar BCSSR to the non-carriers (OR=0.61 [95% CI=0.28-1.34]). There was no significant difference in disease-free survival (DFS) between BRCA2 mutation carriers and patients with sporadic disease. Our results suggest that BRCA2 mutation increases long-term OSR in hereditary BC, which reminds us a new prospect of management of the disease.
BRCA2 Protein
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genetics
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Breast Neoplasms
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genetics
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mortality
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pathology
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Female
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Gene Expression
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Genetic Counseling
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Genetic Predisposition to Disease
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Humans
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Mutation
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Odds Ratio
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Prognosis
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Survival Analysis
8.Impaired phosphorylation and mis-localization of Bub1 and BubR1 are responsible for the defective mitotic checkpoint function in Brca2-mutant thymic lymphomas.
Experimental & Molecular Medicine 2003;35(5):448-453
Breast cancer susceptibility gene, BRCA2, is a tumor suppressor and individuals who inherit one defected copy of BRCA2 allele experience early onset breast cancer or ovarian cancer accompanied by the loss of the wild type allele. Mouse model for Brca2 mutation shows growth retardation and paradoxical occurrence of thymic lymphomas. Thymic lymphomas from Brca2-mutant mice harbor mutations in p53, Bub1, and BubR1, which function as mitotic checkpoint proteins. Therefore, interplay between Brca2 and mitotic checkpoint has been suggested in the maintenance of genetic fidelity, although it has not been assessed whether the unique mutations in Bub1 and BubR1 found in Brca2-mutant mice are responsible for the abolishment of mitotic checkpoint function. This report demonstrates that Bub1 and BubR1 mutant proteins from Brca2(-/-)thymic lymphomas have defects in the phosphorylation and kinetochore localization after spindle damage. Thus, the mutations of Bub1 and BubR1 found in Brca2- mutant mice indeed are responsible for the chromosome instability in Brca2-mutated tumors.
Animals
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BRCA2 Protein/*genetics/*metabolism
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Cell Cycle Proteins
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Cell Transformation, Neoplastic/metabolism
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Mice
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*Mitosis
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Mutation/*genetics
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Phosphorylation
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Protein Kinases/*metabolism
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Protein Transport
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Support, Non-U.S. Gov't
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T-Lymphocytes/metabolism
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Thymus Neoplasms/genetics/*pathology
9.Prevalence of BRCA1 and BRCA2 Mutations in Korean Breast Cancer Patients.
Sei Hyun AHN ; Ui Kang HWANG ; Beom Seok KWAK ; Ho Sung YOON ; Bo Kyung KU ; Hee Jun KANG ; Ji Su KIM ; Byung Kyun KO ; Chang Dae KO ; Kyung Sik YOON ; Dae Yeon CHO ; Jun Suk KIM ; Byung Ho SON
Journal of Korean Medical Science 2004;19(2):269-274
The incidence of breast cancer in Korea has been increasing in recent years, such that it is now the most common female cancer. Breast cancer in Korea is characterized by an earlier age of onset than in Western countries, suggesting that it would be related with genetic background. We assayed germline mutations in the BRCA genes to evaluate their genetic pathology in Korean breast cancer patients. The study subjects consisted of 173 patients at clinically higher risk and 109 unselected patients. Germline mutations in the entire coding sequences of the BRCA1 and BRCA2 genes were analyzed by Conformation-Sensitive Gel Electrophoresis (CSGE), and any aberrantly-sized band was sequenced. BRCA mutations were present in 12.7% of the high risk patients, compared with 2.8% of the unselected patients. Among high risk patients, mutations were most prevalent in patients with a family history of breast or first-degree ovarian cancer (22.1%), followed by those with male breast cancer (20%), bilateral breast cancer (20%), multiple organ cancer including breast (13%) and younger breast cancer patients (aged<35 yr) (8.1%). Moreover, BRCA mutations were detected in 34.8% of patients having two highrisk factors. These findings suggest that BRCA gene mutation analysis should be performed on Korean patients with high-risk factors for breast cancer.
BRCA1 Protein/*genetics
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BRCA2 Protein/*genetics
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Breast Neoplasms/*epidemiology/*genetics
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Female
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Genetic Predisposition to Disease/epidemiology
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Germ-Line Mutation
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Human
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Korea/epidemiology
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*Point Mutation
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Prevalence
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Risk Factors
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Support, Non-U.S. Gov't
10.Study of BRCA1 and BRCA2 gene mutations in human sporadic breast cancers.
Hai-Tian ZHANG ; Yun-Fei LU ; Jian ZENG ; Jian LIN ; Qing-Hua LIAO ; Fu-Qiang WAN
Chinese Journal of Surgery 2007;45(7):480-482
OBJECTIVETo detect the mutations of BRCA1 and BRCA2 in sporadic breast cancer and study the relationship between BRCA1 and BRCA2 mutations and breast cancer.
METHODSBreast cancer tissues of 144 patients and breast tissues of 30 cases of healthy people who were treated from December 2000 to September 2005 were studied. DNA was extracted by the phenol-chloroform method. Fragments of exon 2, exon 3, exon 5, exon 6, exon 7, exon 8, exon 9, exon 10, exon 11, exon 12, exon 13, exon 14, exon 15, exon 16, exon 17, exon 18, exon 19, exon 20, exon 21, exon 22, exon 23 and exon 24 in the BRCA1 gene and exon 10 and exon 14 in the BRCA2 gene were amplified by polymerase chain reaction. Mutation screening was performed by single-strand conformation polymorphism analysis and alterations were confirmed by DNA sequencing.
RESULTSA total of 20 single nucleotide changes in BRCA1 were detected in the 144 cases of breast cancer patients. The total mutation rate was 13.9% and missense mutation rate was 11.1%. No mutation was detected in the BRCA2 and controls.
CONCLUSIONSMutations in BRCA1 may play an important role in evaluation of sick risk, earlier diagnosis and gene therapy of breast cancer in southern Chinese populations.
Adult ; Aged ; Apoptosis Regulatory Proteins ; BRCA1 Protein ; genetics ; metabolism ; BRCA2 Protein ; genetics ; metabolism ; Base Sequence ; Blotting, Western ; Breast Neoplasms ; genetics ; metabolism ; pathology ; DNA Mutational Analysis ; Female ; Humans ; Middle Aged ; Mutation ; Polymerase Chain Reaction ; Polymorphism, Single-Stranded Conformational